Effect of post-growth laser treatment on optical properties of Ga(In)NAs quantum wells

The effects of laser irradiation on the optical properties of GaAsN and GaInNAs quantum wells are studied in detail. Laser treatment is found to affect GaAsN quantum wells similarly to thermal annealing. The most intense photoluminescence is obtained by utilising both thermal and laser treatments. In quaternary GaInNAs, the effects of thermal annealing and laser treatment differ from each other. Thermal annealing of a Ga_0.80In_0.20N_0.02As_0.98 quantum well at 700°C for 10 min shifts the photoluminescence peak by 86 meV towards large photon energies and increases its integrated intensity by a factor of ten. For the same quantum well structure, the luminescence intensity increases by a factor of 2.5 due to laser treatment, whereas the blue shift of the luminescence peak is negligible. The laser treatment effects are observed at laser irradiation intensities encountered in typical photoluminescence measurement conditions. Therefore, the effects of laser irradiation should be taken into account when measuring the optical properties of Ga(In)NAs samples.